DSP library for creating an Android application.?

Question

I am familiar with the basic development of applications for Android and is now assigned the task of making an android application that should perform the functions of a DSP for processing audio. I would like to have some basic knowledge of C / C ++ libraries that I can use with android ndk and embed them in my Android app. I already checked and looked at the many solutions available, but no one satisfied my requirement, please share the links where I can get such libraries that I can use. Sorry if my question is not clear, because I'm new to asking questions here.

Thanks for your reply...!!!